Lead engineer Jean Berlin died in 1975 and the French project was abandoned two years later.

Just a few months after the initial Aerotrain test, in July 1966, the US M-497 Black Beetle made its first test run — it was a much larger vehicle.

Two General Electric engines designed for US fighter jets were mounted to the top of an existing railway car by engineer Don Wetzel and tested successfully. Just a few years later Wetzel made a more permanent mark on the modern world as the inventor of the automated teller machine (ATM).

The M-497 still holds the US light-rail land speed record in the United States (183 miles per hour), nearly 50 years after its inception:

People stopped building jet trains after the 1970s — some countries started going for high-speed rail and some seemed to simply have lost interest, perhaps realising that attaching the engines of an incredibly expensive plane to the top of existing trains was not a viable long-term transport solution.